How ‘Jeweled’ Beetles Get Their Shine
By Andrea Thompson, Senior Writer
posted: 23 July 2009 02:06 pm ET
The metallic green sheen of the jeweled beetle glitters only when certain types of light hit tiny structures on the shell of the insect. Otherwise, the green hue disappears, a new study finds.
While pigments account for the colors of flowers, leaves and other structures in nature, some organisms get their bright hues from the way light interacts with the microscopic structure of their skin, feathers or shells — for example, iridescent butterflies and certain sea creatures. …
The exoskeleton of the brilliant green beetle (Chrysina gloriosa, or Plusiotis gloriosa) selectively reflects left circularly polarized light, or light whose electric field, from the perspective of the observer, has a left-hand corkscrew structure along the direction it is moving.
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